Robotic-Assisted Triple Reaming Technique for Total Hip Arthroplasty in Protrusio Acetabuli

Abstract

We describe a robotic-assisted triple reaming technique during total hip arthroplasty in protrusio acetabuli. This technique uses computerized tomography-based 3-dimensional preoperative planning and intraoperative dynamic referencing to prepare the acetabulum. Two separate surgical plans are created using the robotic workflow. Using the first plan, the protrusio defect is prepared utilizing a reamer that matches the size and location of the defect. Using the second plan, the true acetabulum is reamed, using a reamer that restores the hip center and provides an adequate rim fit. Thirdly, the impacted bone grafts are also reverse reamed using the second plan. The 3-step sequential reaming as well as final insertion of the acetabular component are performed with real-time robotic feedback. The robotic-assisted triple reaming technique can facilitate restoring the hip biomechanics in protrusio acetabuli.

Keywords: Hip centre of rotation; Impaction bone grafting; Protrusio acetabuli; Robotic assisted total hip arthroplasty.

Figure 1

Preoperative radiographs (a) anteroposterior view and (b) lateral view.

Figure 2

Robotic planning for the acetabular protrusio.

Figure 3

Robotic planning for the actual acetabular component.

Figure 4

(a) Reaming the acetabular protrusio and (b) Robotic screen showing completion of the reaming as planned.

Figure 5

(a) Reaming for the actual acetabular component and (b) Robotic screen showing completed reaming as planned.

Figure 6

(a) Autologous bone grafts, (b) Reamed acetabulum, (c) Bone grafts placed in the acetabulum, and (d) After impaction of the bone grafts.

Figure 7

(a) Reverse reaming of the impacted bone grafts. (b) Robotic screen showing the completion of reverse reaming as planned.

Figure 8

(a) Real-time robotic screen confirming the position of the acetabular component insertion, (b) Final component position being confirmed by a robotic probe, (c) After insertion of the acetabular shell, and (d) After insertion of the acetabular liner.

Figure 9

(a) Robotic planning for the femoral component. (b) After insertion of the femoral component.

Figure 10

(a) Immediate postoperative radiograph, (b) and (c) follow-up radiographs. (Arrows point to the acetabular protrusio with impaction bone grafting).